FAIR VALUE MEASUREMENTS: (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2018
Assets and liabilities measured at fair value on a nonrecurring basis
Long-term debt, fair value	$ 90,000		$ 90,000		$ 90,000
Long-term debt	90,000		90,000		90,000
Long-term lease liability	17,505		17,505		$ 0
Long-lived assets			3,005	$ 11,099
Level 2
Assets and liabilities measured at fair value on a nonrecurring basis
Long-term lease liability	17,500		17,500
Nonrecurring | Level 3
Assets and liabilities measured at fair value on a nonrecurring basis
Long-lived assets	$ 702	$ 313	$ 3,005	$ 9,565